Lincoln, ME – Two vacationing Florida residents suffered severe burns when an explosion, possibly from a propane stove or heater, destroyed their cabin on Upper Coldstream Pond early Wednesday.

The man, identified as 51-year-old Rick Pedley, suffered burns to 80 to 85 percent of his body, while 56-year-old Linda Smith endured burns over 60 to 65 percent of her body, officials from the Maine State Fire Marshal’s Office said.

The victims were taken to Penobscot Valley Hospital in Lincoln, where a LifeFlight helicopter picked them up and flew them to Massachusetts General Hospital in Boston. They are in critical condition, a Massachusetts General spokeswoman said Wednesday evening.

Neighbors said they might have heard more than one explosion from the small one-story cabin, which was located on McGregor Road, a dead-end unpaved artery off Transalpine Road.

“I thought it was fireworks,” said Carlos Marini, a Franklin, Mass., resident vacationing this week at a cabin about 50 yards from the Pedley camp. “My wife thought that it was me watching television. And then all these neighbors started banging on my door and telling us we had to get out because there was a fire.”

About 50 yards from Marini’s cabin, Fred Pete of 334 McGregor Road heard a loud boom at about 1 a.m. Like Marini, he saw a huge ball of flame burning the cabin and some trees around it in the thick woods. At the same time, neighbors started calling to warn him of the flames, Pete said.

Pete was met at his door by Galen Pelkey, a friend of Pedley’s who was seeking help with the victims. Pete helped firefighters carry Smith on a stretcher to the PVH ambulance, then helped with Pedley when the second ambulance arrived, he said.

The victims were found in the water, partially clothed. Pete and Marini said they didn’t know whether the explosion propelled them there, or they disrobed and sought the water to relieve their wounds. Steve McCausland, spokesman for the Maine Department of Public Safety, said the victims jumped into the pond to escape the fire.

Pete said the woman was screaming in terrible pain, while Pedley complained of feeling extremely cold. The couple reportedly said they were in bed when the explosion occurred.

Pelkey, who lives a few camp lots away from the fire scene, declined to comment on Thursday afternoon. “We just want to put this behind us,” a woman with Pelkey said.

Pete said he grew up with Pedley but that the accident marked the first time Pete had seen him in four years. He said he believed Smith is from Georgia and that the couple had been together for four or five years. Both were vacationing from Florida.

Investigators are trying to determine exactly what exploded and why, said Sgt. Tim York of the Maine State Fire Marshal’s Office. Whatever it was, the explosion it caused was quite large, he said.

“Every 911 call that was received about it identified it as an explosion,” York said Wednesday, “so it must have been a fairly large explosion.”

The blast was reported at about 1:10 a.m. When Lincoln firefighters arrived, they found the camp almost totally consumed by flames and the victims in the water, which is known locally as the Little Narrows, Fire Chief Phil Dawson said. The fire also heavily damaged an SUV bearing Florida license plates.

“We don’t know exactly what exploded, but we do know that LP gas [propane] was part of the problem,” Dawson said.

Fire Marshal Stu Jacobs was at the scene Wednesday morning trying to reconstruct what happened, Dawson said. He could not be reached for comment.

Nineteen Lincoln firefighters responded to the accident, Dawson said. Mattawamkeag firefighters manned Lincoln’s fire station, while Lee and Burlington volunteer firefighters supplied tankers to help fight the blaze.